"I don't understand why any famous person would ever be on Twitter," he says.

"I had my Aunt Rosie [Rosemary Clooney], who was famous and then not, so I got a lesson in fame early on. And I understood how little it has to do with you. And also how you could use it."

The affable actor talks about fame and more in the December issue of Esquire mag. Some highlights from the chat:

On a fight with Russell Crowe: "I sent him a note going, 'Dude, the only people who succeed when two famous people are fighting is People Magazine. What the (heck) is wrong with you?' "

When entertaining guests at his villa on Lake Como: "At Dinner, everyone puts their phones away. And so there are not a lot of photos of our time there. Because I want us to live them."

George Clooney covers the December 2013 issue of 'Esquire.'(Photo: Phil Poynter)

On Twitter and fame: "If you're famous, I don't — for the life of me — I don't understand why any famous person would ever be on Twitter. Why on God's green earth would you be on Twitter? Because first of all, the worst thing you can do is make yourself more available, right? Because you're going to be available to everybody. But also Twitter. So one drunken night, you come home and you've had two too many drinks and you're watching TV and somebody pisses you off, and you go 'Ehhhhh' and fight back. And you go to sleep, and you wake up in the morning and your career is over. Or you're (a jerk). Or all the things you might think in the quiet of your drunken evening are suddenly blasted around the entire world before you wake up."

On his buddy, Brad Pitt: "For a long time now, Brad has been the biggest movie star in the world. He's bigger than me, bigger than DiCaprio. And I really admire how he deals with that. It's not easy for him. But he tries to be the most honest version of Brad Pitt that he can be. And he also remains unavailable. He's still a giant movie star because you can't get to him. That doesn't mean that I don't think of him as incredibly talented and smart and all those things. But you also can't get to him."